Nice looking base, but one thing you might want to consider. It is illegal to insert something under another robot and lift. While your wedge technically shouldnt violate that if you run into another robot (at least were hoping our wedges dont....), you should consider that if another robot runs up onto that wedge, and gets up as high as the wheels then you go into reverse you will technically be inserting something under a robot and lifting. Just something to consider.
Overall I love the robot. The pic is cool too. I spent a minute looking at that bar that appears to be on the back of the chassis, but yet the chain goes behind it... I thought you had somehow photoshopped it to make an optical illusion until I noticed where the bar actually goes
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